DE2139311A1 - Process for the production of azo dyes - Google Patents

Description

Patent attorneys

Dr. Ing.Walter Abitz
Dr. Dieter F. Morf
Dr. Hans-A. Browns

8 Munich Hu, Hiöuzenaiie.sir. 28

EI DU PONT DE NEMOURS & COMPANY Wilmington, Delaware V.St.A.

Process for the production of azo dyes

The invention is concerned with a one-step process for the production of azo dyes in a reaction mixture containing an aromatic amine, coupler, diazotizing agent and an acidic liquid medium capable of dissolving at least a portion of the amine and the coupler is capable and capable of producing a pH of 4 or less when the mixture is 25 # its Volume of water is diluted, the concentration of the diazotizing agent and the temperature and acidity of the mixture are maintained so that the rate of consumption of diazotizing agent practically equals the rate of formation of the azo dye is.

The invention relates to a one-step process for the production of azo dyes.

Azo dyes were traditionally produced on an industrial scale using a multistage process. This The method consists in preparing a suitable aqueous solution or dispersion of a diazonium salt a primary aromatic amino compound in a reaction vessel, the preparation of a suitable aqueous

209817/1451

OR-4729

Solution or dispersion of a coupling compound in a second container and either the addition of one of these compositions to the other or their mixing in a third container, occasionally with the simultaneous addition of a pH modifier to bring about the coupling. Since diazonium salts are thermally unstable, it is necessary to work at a low temperature, usually below 10 ^° C., so that the use of ice is necessary. Since it is not always possible or practical on an industrial scale to keep the diazo salt at temperatures below which decomposition occurs, the azo dyes obtained can contain impurities from decomposed diazo compounds and are not always uniform in terms of quality.

It also requires the usual method of manufacture of azo dyes that the coupling reaction vessel is a Has reserve volume to accommodate both reactive masses. Moreover, there is the diazotization reaction "must be completed before the coupling can be brought about k, the total diazotization and coupling reaction time long, so that, as a whole, the production cost is high.

Some azo dyes can be made in one-step processes will. US Pat. No. 2,478,768 describes a process for the production of an azo lacquer, the Diazotization, coupling and lacquer formation can be carried out in a medium at a pH above 6. A watery one Acid solution of a lacquer forming agent and / or an azo color component becomes an aqueous alkaline one

- 2-

209817 / U51

OR-4729 I.

Solution of a soluble nitrite and at least one azo color component added while maintaining the reaction mixture at a pH of at least 6.0. the described couplers are of the phenol type, which requires relatively high pH for coupling and the obtained Azo inks must contain at least one water-solubilizing acid group.

In US Pat. No. 2,478,767, a one-step process is used for Production of an azo dyes described; Diazotization and coupling are carried out in the same aqueous reaction medium carried out by mixing aqueous solutions of the diazo and coupling components in a container, while maintaining a pH of the mixture of 6.0 to 7.2. In particular, an aqueous mineral acid solution is used a diazo component, the Irish! of water soluble making acid groups and an aqueous alkaline solution of nitrite and ß-hydroxynaphthoic acid, ß-hydroxynaphthoe-o-anisidid or acetoacetanilide as quickly as the diazotization occurs, mixed to a limited extent Produce number of dyes that are useful as pigments.

? 418 416
US Pat and (2) the pH of the mixture is increased above 4.0 to induce coupling. Such a process can result in the decomposition of some of the diazo compound prior to coupling.

- 3 -

209817 / US1

It has been found that azo dyes can be obtained easily and economically in a one-step process can be made by

(a) a diazotizable aromatic amine,

(b) a coupling compound composed of active methylene compounds and / or aromatic amines which cannot be appreciably diazotized are in the reaction mixture and at least one unsubstituted position is in the ortho or para position sau of the amino group and

(c) a diazotizing agent

are brought into contact and reacted simultaneously in a reaction mixture which contains (a), (b), (c) and an acidic liquid medium which is capable of dissolving in each case at least a part of (a) and (b) and of generating a pH of 4 or less is capable if the reaction mixture is diluted with 25 i ° of its volume of water, while the concentration of the diazotizing agent and the temperature and acidity of the reaction mixture are maintained so that the rate of consumption of diazotizing agent is practically the same is the rate of formation of the azo dye.

According to the invention, a diazotizable amine, azo dye coupler, are used in a liquid acidic reaction medium and diazotizing agents are brought together. As in the usual two-step process, that of the invention requires Process about 1 mole of diazotizing agent per mole of diazotizable amine, the amine and the coupler are present in approximately equimolar proportions. The azo dye The diazotizing agent is thus formed at least partially in the two dye-forming intermediates dissolved state, containing acidic liquid

- 4 209817 / U51

OR-4729 &

Phase is present. The diazotization of the diazotizable aromatic amine and the instantaneous coupling of the diazotized amine to the coupling compound can take place under relatively mild nitrosation conditions, e.g. with nitrous acid in formic acid, acetic acid or similar moderately strong organic acid media. There aromatic amines such as 2,6-dichloro-4-nitroaniline, the normally stronger acid for diazotization require, for example nitrosylsulfuric acid, can also be used in the above organic acid medium according to the method of the invention, -appears a simple diazotization coupling sequence does not seem to be the only possible pathway. So be it pointed out that according to the invention Azo dyes made by processes do not necessarily involve the formation of a diazo intermediate.

The process can be carried out batchwise or continuously. It is appropriate to use diazotizing agents or its To mix precursors with a mixture of diazotizable amine and coupler in the acidic liquid medium. That Acid medium can also be used as a separate stream with a mixture of diazotizable amine, coupler, liquid medium and diazotizing agent precursors are mixed.

As a further variation, separate streams of the specified constituents, preferably in liquid and / or solution form, can be brought together at the same time.

According to another variation, the diazotizing agent as such can be incorporated into the liquid, diazo dye components containing medium are introduced. Such a means

- 5 -209817 / U51

OR-4729 ζ

Nitrogen trioxide (N ₂ ^) »mixed-in anhydride of nitrous acid and another acid, such as" for example nitrosylsulfuric acid or kitrosyl chloride, an ester of nitrous acid, such as ethyl nitrite or tert-butyl nitrite or nitrous acid in a suitable carrier solvent.

The diazotizing agent can be in the liquid medium, which contains the azo dye coraponents, are formed, for example by adding nitrous acid to the liquid medium from a nitrous acid salt or ester a suitable reaction agent such as an acidic material. The preferred type of education of the diazotizing agent is the addition of one Nitrous acid salt, e.g. sodium uranium nitrite, to the liquid Medium containing acid strong enough to convert the nitrite to nitrous acid.

The liquid acid medium used is said to have the ability have to dissolve sufficient amounts of both the diazotizable amine and the coupler so that the one-step Azo dye formation can proceed at reasonable rates.

It is normally desirable that the acidic liquid medium dissolve at least about 1 # its weight of each of the diazotizable amine and the coupler. More expediently, the liquid should dissolve more than 10 5 ^, preferably more than 50%, of each of these reaction components. The amount en liquid used may be merely sufficient to yield a stirrable slurry, or in particular in cases in which the reaction component is very soluble, can be enough liquid be used to the

- 6 209817/1451

OR-4729 J.

Completely dissolve rejection components. The solubilities the reactant in the one used to conduct the one-step azo dye preparation process acidic liquid medium can be determined using standard methods. However, testing as to the minimum practical solubility of the diazotizable amine and coupler in the acidic liquid medium can be easily and quickly done using the same standard experiments that are used to follow the progress of the reaction. The presence of the diazotizable amine in the acidic liquid Phase can be achieved by adding nitrite, then taking a sample of the solution and examining whether it occurs of the diazotized intermediate product by spot test coupling with standard coupler solution, e.g. alkali Η-acid, can be determined. If the coupling with the coupler component is instantaneous in the original reaction, the diazo compound does not can be determined, this attempt can be made for the minimum feasible solubility with the same acidic liquid medium, however, can be carried out without any coupler present or the reaction mixture can be analyzed for the presence of the desired azo dye product. The presence of the coupler in solution can easily be obtained by testing a sample with standard diazo solution, e.g. diazotized] p-nitroaniline, be determined.

It is preferred that both the diazotizable amine and the coupling compounds are highly soluble in the liquid medium, but that the azo dye product is much is less soluble than its components in order to ensure the formation of a pure dye and the recovery of the produced

- 7-209817 / US1

OR4729

.Dye to facilitate. Favor such conditions the production of a dye of superior color quality with little or no need for subsequent Cleaning consists.

If a nitrite is added to the reaction mixture to form the diazotizing agent, it should contain acid in excess of the amount necessary to convert the nitrite salt to nitrous acid. The excess acid should be sufficient to produce a pH of 4.0 or less when a sample of the mixture is diluted with 25% of its volume of water.

Typical acidic liquid media include aqueous mineral acids such as hydrochloric, hydrobromic, phosphoric and sulfuric acids, normally liquid organic acids with a primary ionization constant at 25 ⁰ C of at least 1.3 × 10, such as formic acid, acetic acid and propionic acid and Mixture «of it. Acetic acid is preferred because of its availability and cheapness. However, if aromatic amines, which are usually only with difficulty, "Uazotierbar, for example 2,6-dichloro-4-nitroaniline and be used _{i 5} L 4-dinitroaniline, formic acid is, for example, as a 88 #ige aqueous solution is preferred.

Liquids suitable here can be geroics of normally liquid components as well as mixtures of components, which become liquid after mixing. Suitable normally liquid components include carboxamides, such as formamide, Ν, Η-dimethylformamide, N, H-dimethylacetamide, Tetramethylurea and cyclic amides,

209817 / U51

OR-4729 J.

such as N-Methylbutyrolaetamj ketones, such as acetone and MethyläthylJcetonj aliphatic glycols, such as ethylene glycol and polyethylene glycols and their ethers, eg Monoalkylätba? of ethylene glycol and polyethylene glycols; cyclic ethers, for example tetrahydrofuran, p-dioxane and ra-bioxane; nitrogen-substituted phosphorus triamide compounds, such as, for example, F, N, IT ·, N ^f , N ", N" -hexate, methylphosphorus triamide, polar nitrogen- and halogen-substituted hydrocarbons, such as, for example, nitrobenzene, chloroform, tetra-chloroethylene, o-dichlorobenzene and 2,4,5-trichlorobenzene Components which, where necessary, provide the required acidity of the liquid medium include mineral acids, for example hydrogen chloride, hydrogen bromide, phosphorus and. Sulfuric acid; organic acids such as formic acid, acetic acid and propionic acid; Hydroxycarboxylic acids, e.g. Glycolic acid and lactic acid; Aryl carboxylic acids, for example benzoic acid and toluic acid and arylsulfonic acids, for example p-toluenesulfonic acid.

Water, a preferred liquid component, ketones, Glycols and glycol ethers can be used in combination with an organic or a mineral acid component will. Dimethylformamide, another preferred liquid, other carboxamides, cyclic ethers, and hexamethylphosphoric triamide are preferably combined with organic acids.

Although many of the foregoing components are costly their cost is due to their high solubility and the reduction in time and labor costs more than outweighed when used in this procedure. The cost of using many of these components are easy to obtain by extraction and

- 9 209817/1451

OR-4729

Distillation methods reducible.

Although the invention broadly applies to manufacture of azo dye is applicable, refers an important embodiment on the manufacture of Azo dye pigments which are suitable as disperse dyes and which are free of such water-solubilizing agents Groups such as carboxy and sulfo groups. According to amine and coupling components used in the invention can therefore be free from such groups.

Typical diazotizable aromatic amines that Suitable for the present process include carbocyclic and heterocyclic aromatic amines, the are unsubstituted in the core or are core-substituted with one or more groups, such as nitro, Chlorine, bromine, alkyl, alkoxy, cyano, carboxy, keto, arylazo, acylamino, sulfo and onium groups. These Substituents can be present in combination with the aromatic arain, which is preferably an aniline.

Examples of these diazoic aasins are 4-lfitroaniline; 3- nitroaniline; 2-nitroaniline; 2-chloro-4-nitroaniline; 2,6-dichloro-4-nitroaniline; 2,6-di) roia-4-nitroaniline; 4-aminoacetanilide; 2-kitro-4-methylaniline; 4- (o-tolylazo) -2-methyl aniline; 4-Aminoazolieiizolj 4-nitrophenylazo-1-naphthylamine; 2,4-dinitroaniline; 2,5-diraethoxyaniline; 2-cyano-4-nitroaniline 2,4-dinitro-6-chloroaniline; 2,5-diethoxyaniline; 4-cyanoaniline; 2-chloroaniline; 3-chloroaniline; 4-chloroaniline 2,5-3) chloroaniline; 4-chloro-2-nitroaniline; o-toluidine | p-toluidine; S-chloro-aminotoluene; 6-chloro-2-aminotoluene; 4-chloro-2-aminotoluene; 4-nitro-2-aminotoluene; 5-nitro-2-aniiotoluene; m-amlnobenzyl alcohol; 2,3-xylidine; m-xylidine; 2,4-xylidine?

- 10 - 209817 / US1

OR-4729 4tf

p-xylldine; 2,5-xylidine; p-butylaniline; p-dodecylaniline; n-formyl-m-phenylenediamine; n-oxalyl-m-phenylene / j ^a ]? - iinodiphenylamine; p ~ aminoacetanilir3 .; Oxalyl-p-phenylenediamine; 2-amino-4-acetylaminotoluene; Benzidine; 3.3 ^! -Dichlorobenzidine; 2-nitrobenzidine; Aniline; 4 _s 4'-methylene-di (iD-toluidine); o-anisidine; o-phenetidine; 4- ^ itro-2-aminoanisole; 5-nitro-2-aiDinoanisoli 4-chloro-2-aminoanisbl; p ~ phenetidine; p-anisidine; 1,3-di ~ (p-aminop! Ienoxy) propane; 4-ATnino-4-methoxydiphenylarain; 2 ~ nitro-4-aminoaaisol; 3-nitro-4-amino anisole; Psp ^ kiiodiaxiilin; p _? p ⁵ -oxydianiline 4-atainodiphenyl ether; 5-methyl-o-anisidine; 2 = -lth.oxy ~ 1-naphthob.ylamine; a-lfephhtliylamine; Dianisidine; 4-carbometlioxyamino-2,5-diethoxyaniline; 4-ben25oylamino-2,5-diethoxyaniline; Di- (4 ⁹ -amino'benzoyl) -iD-plienyleiidiaiiiin; 3-alino-4-methylbenzontril; 4- (picoliny! Amino) -2,5-diethoxyaniline; 1 - (m-AiDinophenyl) -3-methyl-5-pyra2-olone; 2 ~ cyano-4-nitroaniline; 4,4'-diphenyl sulfone; 4-methylsulfonylaniline? 1 -Aniino-2,3, 4,5-tetracyanooyclopentadien; 2- (o-Ami2io ~ phenyl} -2,1,3-benzotriazole; _"? 2.1 3" 2- (o-Aiaiiiophenyl) = · α, β-naphthotriazole, 4-Aminobenzophenonj 4-Aiainoacet © phenone 4? - (p-Uitrophenyl8Zo) -2-, 5-diinetlioxyanili2i? 4 ~ (2,6-Diclilor- »4-nitrophenylazo) -2,5-diraethoxyaniline; 2,4 ~ dicyanoaniline; 3-chloro-4-cyanoanilia; o -Aainobenaotrifluorid ι 5-C! Ilor ~ 2-aminobensotrifLuorid? Dehyßrothio-p-toliiidin; 4 ^ft -Aiaino-2-cb.lorbenzophenonj 4 '-Aaiino-2,4 ~ dicalorbenzophenone | 2-Amino-4' -bromben ^! -Amino ~ 3-broii ~ 4 phenone; 2'-araino-2,5-dimethylbenzoplienone5 4 »araino-4'benzophenone; 2 ~ amino-4 ^f -Eethoxybenzophenonj 2'-auino-4-inethoxy-2,5-dimethylbenzopb .enons 3 * -amino-3 ₉ 4-dimeth 'oxy benzophenone; 4'-araino-5-'chlor-2-iaethoxybenzophenone; 4-amino-4 -siethoxybenzophenone; 3-amino-4'-methoxy also phenone; 2 -Auino-2 ^l -nitrobenzophenone; 2-alaino ~ 3 ^l »nitrobenzophenone; oc-arainoanthraquinone; ß-arainoanticaliquinone;

- 11 -209817 / U51

4-amino-4'-nitrobenzophenone;4'-amino-2,4-dinitrobenzophenone;4'-amino-2,4-dinitrobenzophenone;4'-amino-4-methyl-3-nitrobenzophenone;4-amino-4'-butylbenzophenone;4-atnino-4'-propoxybenzophenone;2-amino-4'-fluorobenzophenone;4-araino-2-propylbenzoph.enone;2-amino-4,5-dipropoxybenzophenone;2-Alibino-5-bromobenzophenone;4-araino-3-chlorobenzophenone;2-amino-4,5-dichlorobenzophenone; A - amino-3,5-dibromobenzoplienone; 4-amino-2-methylbenzophenone j 2-amino-5-methylbenzophenone; 2-amino-4,5-dimethylbenzophenone; 3-Ainino-2,4- <3iiDethylbenzoph.enon; 2-amino-4 »5-dlmethoxybenzophenone; 2->amino-4-i-ethoxybenzophenone;3-amino-5-nitrobenzophenone; 3-anjino-4 - tQ © ethyl-5-nitrobenzophenone; 2-amino-6-ynethyl-3-nitrobenzophenone 2-araino-3,5-dinitrobenzophenone; 2-AtDino-4-niethyl-3 »5- <3 initrobenzophenone; 2-amino-5-fluoro-benzophenone; 4-Cb.lor-2- (p-chlorophenjlsnlfonyl) aniline; p- (p-bromophenylsulfonyl) aniline; 2-chloro-4 »(pb.enylsulfonyl) aniline; 2-chloro-6- (phenyl-sulfonyl) -anilln; 3-chloro-2- (phenylfulfonyl) aniline; 3-chloro-4- (plienylsulfonyl) -8niline; 5-chloro-2- (phenylenesulfonyl) aniline; 4-chloro-3- (phenylsulfonyl) -. Aniline; 4-chloro-2- (phenylsulfonyl) aniline; 2-bromo-4- (phenyleulfonyl) aniline; p- (2,4-dichlorophenylsulfonyl) sailin; p- (2,5-dibromophenylsulfonyl) aniline; p ~ (3,4-dishlophenylsulfonyl) aniline; 5-chloro-2- (p-tolyl_sulfonyl) aniline; p- (p-tolylsulfonyl) aniline; p- (p-propylphenylsulfonyl) aniline; p- (p-fluorophenylsulfonyl) aniline; p- (3-chloro-4-methoxyphenylsulfonyl) aniline; p- (2,4-dimethoxyphenylsulfonyl) aniline; p- (3,5-dimeth / oxyphenylsulfonyl) aniline; p- (p-methoxyphenylsulfonyl) aniline; p- (p-ethoxy phenyl sulphonyl) -a nil in; p- (2-methoxy-4-nitrophenylsulfonyl) aniline; o- (p-methoxyphenylsulfonyl) aniline; p- (o-methoxyphenylsulfonyl) aniline; p- (p-nitrophenyl sulfonyl) aniline; 2-nitro-3- (phenylsulfonyl) aniline; 2-nitro-5- (phenylsulfonyl) aniline; 2,4-dinitro-5- (phenyl-

- 12 - 2098T7 / U51

OR-4729 43

sulfonyl) aniline; 2-nitro-4- (p-nitrophenylsulfonyl) aniine; 2-nitro-4- (ra-nitrophenylsulfonyl) aniline; o- (o-Mt ro phenyl sulfonyl) enil in; 2-Efi tr o-4- (phenyl sulfonyl) aniline; 2-nitro-4- (p-tolylsulfonyl) aniline; 2,6-dinitro-4- (p-tolylsulfonyl) aniline; 4- (p-butoxyphenylsulfonyl) -3-ethylaniline; p <2,5-xylylsulfonyl) aniline; p- (2,4-xylylsulfonyl) aniline; p- (2,4-dinitrophenylsulfonyl) aniline; 2,4-dichloro-5- (phenylsulfonyl) aniline; 2,3-diethyl-4- (phenylsulfonyl) -aniline and 2,5-eiffiethoxy-4- (phenylsulfonyl) -aniline. "

Heterocyclic diazotizable amines can also according to of the invention can be used. Some typical compounds are listed below: 2-aminobenzothiazole; 2-amino-4-chlorobenzothiazole; 2-amino-4-brorabenzothiazole; 2-atnino-4-nitrobenzothiasol; 2-amino-4-cyanobenzothiazole; 2-amino-6-broinbenzothiazole; 2-amino-6-cyanobenzothiazole; 2-ATnino-6-nitrobenzothiazole; 2-amino-6- (trifluoromethyl) benzothiazole; δ-acetyl-aminobenzothiazole; 2-amino-6- (trifluoroacetyl) benzothiazole; 2-amino-6-valerylbenzothiazole; 2-amino-6- (β-hydroxypropionyl) benzothiazole; 2-amino-6- (cyclohexylcarbonyl) benzothiazole; 2-araino-6-p-toluoylbenzothiazole; 2-amino-6- (o-chlorobenzoyl) benzothiazole; 2-amino-6- (p-bromobenzoyl) benzothiazole; 2-amino-6- (m-nitrobenzoyl) benzothiazole; 2-amino-6- (methylsulfonyl) benzothiazole; 2-amino-6- (2-hydroxyethylsulfonyl) benzothiazole; 2-amino-6- (propylsulfonyl) benzothiazole; 2-amino-G-cyclohexylsulfonylI-benzothiazole; 2-amino-6- (phenylsulfonyl) benzothiazole; 2-amino-6- (o-tolylsulfonyl) benzothiazole; 2-amino-6- (m-chlorophenylsulfonyl) benzothiazole; 2-amine-6- (p-bromophenyl9ulfonyl) benzothiazole; 2-amino-6- (iD-nitrophenylsulfonyl) benzothiazole; 2-amino-6- (ethoxycarbonyl) benzothiazole; 2-amino-6- (butoxycarbonyl) benzothiazole; 2-amino-6- (trifluoromethylsulfonyl) benzothiazole; 2-amino-4-bromo-6-nitrc> benzothiazole; 2-atnino-

- 13 -209817 / U51

OR-4729 Ή

4,6-dinitrobenzothiazole; 2-amino-4,6-dicyanobenzothiazole; 2-amino-6-bromo-4-methylbenzothiazole; 2-amino-4-methoxy-6-nitrobenzothiazole; 2-amino-6-bromo-4-propoxybenzothiazole; 2-amino-4-cyano-6-nitrobenzothiazole; 2 ~ amino-6-chloro-4-cyanobenzothiazole; 2-amino-6-chloro-4-nitrobenzothiazole; 2-amino-6-brora-4-cyanobenzothiazole; 2-Amino-6-cyano ~ 4- "methylbenzothiazole;2-Amino-6-methyl-4-nitrobenzothiazole;2-Amino-6-raethoxy-4-nitrobenzothiazole;2-Amino-6-butoxy-4-chlorobenzothiazole; 2 -Amino-4-chloro-6-methoxybenzothiazole; 2-? Amino ~ 4-bromo-6-methoxybenzothiazole; 2-amino-4,6-dichlorobenzothiazole; 2-amino-4,6-dibromobenzothiazole; 2-amino-4 -methyl-6- (trifluoromethyl) -benzothiazole; 2-amino-4-methyl-6-propionylbenzothiazole; 2-amino-4-chloro-6- (methylsulfonyl) -benzothiazole; 2-amino-6- (methylsulfamoyl) -4 -nitrobenzothiazole; 2-amino-4-chloro- (cyclohexy8ulionyl) -benzothiazole; 2-amino-4-bromo-6- (ethylsulfonyl) -benzothiazole; 2-aiaino-K, N - dimethyl-4-nitro-6- benzothiazolesulfonamide; 2-amino-N-benzyl-4-chloro-N-ethyl-6-benzothiazolesulfonamide; 2-amino-4-bromo-N-ethyl-6-benzothiazolesulfonanilide; 2-amino-N, IT-dipropyl-4- methyl-6-benzothiazolesulfonamide; 2-amino-4-chloro-6- (methoxycarbonyl) -. benzothiazole; 2-amino-4-bromo-6- (butoxycarbonyl) -benzothiazole; 2-amino-6-benzoylbenzothiazole; 2-amino -6-acetylbenzothiazole;. 2-amino-li, N-dibutyl-6-ben zothiazolesulfonamide; 2-amino-N- * ethyl-6-benzothiazolesulfonamide; 2-araino-2f-butyl-2i-meth.yl-6-benzothiazolesulfonamide; 2-amino-N-benzyl-lί-ethyl-6-benzothiazolesulfonamide; 2-amino-! I-benzyl-6-benzothiazolesulionamide; 2-amino-N-isopropyl-N ■ -methyl-6-benzothiazolesulfonamide; 2-amino-N-isobutyl-6-benzothiazolesulfonamide; 2-amino-N, Ή- diethyl-6-benzothiazolesulfonamide; 2-amino-lf-sec.-butyl-6-benzothiazole suMbnamide; 2-amino-Hf, II-dimethyl-6-benzothiazolesulfonamide; 2-amino-ii, N-dipropyl-6-benzothiazolesulfonamide; 5-nitro-2-aminothiazole; 5-methylsulfonyl-2-aminothiazole; 5-benzoyl-2-aminothiazole; 2-aminoimidazole; 4,5-dicyano-2-

- 14 -

209817 / U51

aminoimidezole; 4i5-3) iphenyli? -Aiiiinothiazole; 3-aminopyridine; 2-aminapyridine-IT-oxyä; 2-alinothiophene; 2-AinIno-3s4- "thiadiassol; 2-AiaIno-3,5-tmadiazolj 2 ~ AtQinobenziiBiä8Zol; 3-Amino-1,2,4-triazoi; 3-As3inobenzisothiaaol? 3-Amino-5 ~ chlorobenziso thiazole; 3 -Amino-5-siLLfo "bensieotliiazole; 2 ~ AmIno-3 ₅ 4-oxa-diazole; 2-Amino-3-cyano-tetrahydroben25tMopheiij 3-An3ino-car "bazole |

Cationic groups, diazo containing compounds which are useful herein are the following _s

ainino-5-phenylphenylphenachloride; 3 ₉ 7-diamino ~ 2, 8 => d imethyl-5 ~ phenylphenazinium chloride; 3-Amino-7-diethylamino =>2-ethyl-5-phenylphenaziniximchlorid; / 2- (p-Atninobenzoyl) -ethyl / ->tri-aethylaramoniuinchlorid; 3- (p-AminobensQyl) propyltriethylammonium bromide; (4-Amino-3 - 'broiHphenaoyl) -trimethylphenyl chloride j (4-ATDino-2,5-diiaethylphenacyl) -tri-methylate-quinonium chloride; (4-Aniino-2-chlorophenacyl) ~ tri! AethyloiDinoniiimolilorid j (4- = Amino ~ 3 j 5-dibromophenacyl) ~ trimethyla! Amoniiirachlorid j 2- (p-AiDino- = »ßtyryl) -1-RaethylpyridiniuiniBethosulfat | 2 ~ (p »aminostyryl) -5-ethyl-1 -inethylpyridiiiiiiffimethoBulfst? (p-Arainophenaoyl) -dimethyl- (2-hydroxyethyl) -aB! iiHoniufflchlorid ₉ - »sulfate and -» phosphati (3 '~ Ainino-4 - niethylpheiiaeyl)' - triTaethylaiBiDOiiiuiBöhloriä | (4 ⁸ ^ Ataino-3 ^l -CQlorphenacyl) -diia @ thylbenzylainiHoniurasulfat | 4 ⁸ ~ aaino-2 *, -5 ^t ~ diraethylp! Ienaoyl) -diffiethyl (2-hydroxyethyl) '- aiamonium phosphate5 (3-amino-'4-esethoxyphenacyl) ->trinethylamffloniuachloride; (p-Araino-a-methyl-phenaeyl) -trimethylammonium chloride.

Some typical aromatic aajinocarboxylic acid · = and aaino · = sulfenic acid derivatives for use as diazo components are the following:

Antisranilic acid, 4-chloroanthranilic acid | p-alainobenzoic acid m-aminobenzoic acid? 4 ~ aminosalicylic acid; 5 orthanilic acid; Metanilic acid; Sulfanilic acid 4-chlorometanilic acid |

209817 / U5T

OR-4729

6-chlorometanilic acid; 2-amino-1-chlorobenzenesulfonic acid; 2,5-diehlorsulfanilic acid; 2-amino-5-nitrobenzenesulfonic acid; 3-chloroaniline-5-sulfonic acid; 3-amino-5-chloro-o-toluenesulfonic acid; 2-aminotoluene-5-sulfonic acid; 2-amino-6-chlorotoluene-3-sulfonic acid; 3-amino-6-chloro-toluene-2-sulfonic acid; 2 ~ chloro-5-aroinotoluene-4-sulfonic acid; 3-aminotoluene-6-sulfonic acid; 4-aminotoluene-3-sulfonic acid; m-xylidinesulfonic acid; 4,6-diamino-m-toluenesulfonic acid; 4-acetylaminoaniline-2-sulfonic acid; 2- (p-aminoanilino) -5-nitrobenzenesulfonic acid; 6- (p-toluidino) metanilic acid; 5-ainino-2- (p-ynethoxyanilino) -

L · benzenesulfonic acid; 1-amino-2-naphthalenesulfonic acid; 5-amino

1-naphthalenesulfonic acid; 5-amino-2-naphthalenesulfonic acid; 8-amino-2-naphthalenesulfonic acid; 8-anjino-1-naphthalenesulfonic acid; 5-acetamido-8-atnino-2-naphthalenesulfonic acid; 8-acetaraido-5-amino-2-naphthalenesulfonic acid; 2-amino-1-naphthalenesulfonic acid; 6-amino-2-naphthalenesulfonic acid; Aniline-2,5-disulfonic acid; 8-amino-1,6-naphthalenedisulfonic acid; 7-amino-1,3-naphthalenedisulfonic acid; 6-amino-1,3-naphthalenedisulfonic acid; 4.4 ^l -diamino-2.2 ^l -stilbene sulfonic acid; 4,4'-Iarainodiphenyl-2,2 ^t -disulfonic acid; 3,3'-dimethyl-4,4'-diaminodiphenyl-6,6'-disulfonic acid; 4-methoxymetanilic acid; 4-methoxy-6-nitrometanilic acid; 2-Xthoxy-1-naphthylamine-6-sulfonic acid; 6- (p-aminobenzamido) -1-naphthol-

w 3-sulfonic acid; p- (p-aminophenylazo) benzene sulfonic acid;

p- (4-Aniino-3-methoxyphenylazo) -benzenesulfonic acid; 4- (4-araino-m-tolylazo ) -m-toluenesulfonic acid; 2-hydroxy-5-ainobenzoic acid; 1- (m-amino phenyl) -5-oxo-2-pyrazolone-3-carboxylic acid; Dehydrothio-p-toluidinesulfonic acid.

Suitable coupling components according to the invention are (1) aromatic amine compounds that are not diazotizable Amino group or a relatively non-reactive amino group compared to the amino group of the diazo component contains a ^ and (2) Compounds having an active methylene group

- 16 -209817 / U51

OR-4729

Usually the cheapest have aromatic alien compounds a tertiary nitrogen atom adjacent to the nucleus and an unsubstituted core position in the ortho position or, preferably, para to the tertiary nitrogen atom

Substituents on the tertiary nitrogen atom can be alkyl radicals with 1 to 3 carbon atoms, such as methyl, ethyl and propyl radicals, preferably methyl or ethyl radicals; Hydroxyethyl radicals; Cyanoalkyl radicals with 2 to 4 carbon atoms, such as gyanomethyl, ß-cyanoethyl or 2-cyanopropyl radicals, preferably S-cyanoethyl radicalsj aeyloxalkyl radicals in which the acyl group is an aliphatic acyl radical with 2 to 5 carbon atoms, e.g. acetyl, propionyl and butyryl radicals preferably an acetyl radical or arylacyl radical having 7 to 10 carbon atoms, such as, for example, benzoyl, toluyl or xyloyl radicals; preferably a benzoyl radical, and wherein the Alkyanteil having 2 to 4 carbon atoms group, for example a Ithy! (preferred), and propyl group be _t.

typical tertiary amines are: Dlethylaniline, Dläthyl-mtoluidin; Di- (n-propyl) -o-toluidinj F-methyl-N- (2 • «cyanoethyl) aniline; 2T, N-bis (2 ^f -cyanoethyl) aniline; U-methyl-K- (3 ^f -eyanopropyl) -m-toluidine; ! K "-GyanoEiet iyl-N- (2 ⁸ -acetoxyäthyl) aniline; IT, LI-bis (2 ^l -acetoxyäthyl) aniline; ET, IT-bis (3 ^f -butyryloxypropyl) -m-toluidine; U, N-bis- (2'-ftenzoyloxyethyl) -m-toluidine} IT, ir-bis- (2-polyoxyethyl) -m * oluidine, li- (2-cyanoethyl) -li- (2 ^f -benzoylomethyl) -aniline; N-ethyl-lf- (2x-cyanoethyl) -aniline; N-ethyl-F- (2x-cyanoethyl) -m-toluidine; N- (2x-cyanoethyl) -U- (2'- hydroxyethyl) -aniline; 2- (F-ethylanilimO-ethanol; Phenyläiäthanolarain? Ιί, 1ί ~ Βΐ8- (2-hydroxyethyl) -m-toluidine; li- (2-Gyanoäthyl) -N- (2 ^s -mesitoyloxyäthyD-aniline; N, H * -bis- (2 »-pivaloyloxyethyl)» anllln; m-chlorodimethylaniline.

- 17 -209817 / U51

Suitable tertiary amines can have other substituents. When other substituents are used, a preferred position for at least one of these substituents is m-position to the tertiary araine group. Other substituents can be the following: methyl radicals; Alkoxy radicals with 1 or 2 carbon atoms and acylated amino groups in which the acylation group is an arylcarboxyacyl radical with 7 to 10 carbon atoms, such as, for example, a bensoyl, toluyl, xyloyl and mesitoyl radical, preferably a benzoyl radical, alkanesulfonyl radical with 1 to 3 carbon atoms * such as, for example Methanesulfonyl, ethanesulfonyl and propanesulfonyl, preferably a methanesulfonyl, or arylsulfonyl with 6 to 7 carbon atoms, such as benzenesulfonyl or p-toluenesulfonyl (preferred). Other compounds suitable here include: IT, H-bis- (2'-acetoxyethyl) -N ^f -benzoyl-ra-phenylenediamine, If, If-bis- (2 ^l -ben2oyloxyethyl) -! I ^t -benzoyl-m-phenylenediamine ; 2-methoxy-5-benzoylamino-li, IT-diethylaniline; Ν, ΒΓ-bis- (2 * -benzoylethyl JH ^ tnethansulfonyl-m-phenylenediamine and ΪΓ, N-bis- (2 -benzoyloxyethyl ) -Ή '-tosyl-m-phenylenediaroin;' H, N-bis- (2J -acetoxyethyl) -N ^l -methanesulfonyl-m-phenylenediamine;! «■, li-dimethyl-a-methoxy-S-methylaniline; N, N-bis (2-hydroxyethyl) -2-methoxy-5-chloroaniline; N , li-dimethyl-2,5-dimethoxyanilineϊ N-methyl-N- (2,3-dihydroxypropyl) -2-chloro-5-methylaniline; N- (2-methoxyphenyl) morpholine; N-methyldiphenylamine; H, li- (2-hydroxyethyl) -2-chloro-5- (p-nitrobenzamido) aniline; K-ethyl-2-chloro-5 »(2,4-dimethoxybenzamtdo) aniline; N- (2-cyanoethyl) - 2.5 ~ d imethoxyaniline; K "- (2-cyanoethyl) -2-methoxy« 5-benzaa »ido) -aniline; N-ethyl-li (2-cyanoethyl) -cresidin;: N, N-bis- (2-cyanoethyl) -

m-anisidine; N, NI) imethyl-N ⁱ - (o ~ anisoyl) -m-phenylenediamine; 3 * - (dimethylamino) benzalldine; II-methyl-N- (2,3-dihydroxypropyl) -m-toluide in; if- (2-cyanoethyl) -o-chloroaniline N- (2-cyanoethyl) -N- (benzoyloxyethyl) -aniline; ii-A * ethyl-N- (2-cyanoethyl) aniline.

- 18 209817/1451

OR-4729 13

As can be seen from the foregoing, the coupler may contain nucleus-substituted water-solubilizing groups such as carboxy and sulfo groups. ^s

Compounds with activated methylene groups which are used as coupling compounds can be selected from the following compounds, for example. ß-diketones, for example benzoylacetone, 1,3-cyclohex: andione and 1,3-per-naphthalenedione; β-keto esters, for example ethyl acetoacetate, diethyl malonate, phenylecetoacetate, methyl 4,4,4-trifluoroacetoacetate and methyl p-nitrobenzoyl acetate; ß-ketoamides, for example acetoacet-4 ^f -chloranilide, acetoacetotoluidide; Benzoylacet-3 ^f -nethoxyanilide, benzoylacet-ajß-naphthylaraid and N, N'-ditolyltnalonamide; β-ketonitriles, for example benzoylacetonitrile, 2'-thenoylacetonitrile, anisoylacetonitrile, 1-naphthoylacetonitrile and p-nitrocinnamoylacetonitrile; Anilides of cyanoacetic acid, for example 2-gyanoacetanilide, 2-cyano-p-8cetanisidide and 2-cyano-4 ^l -nitroacetanilide; heterocyclic β-ketoamides, for example barbituric acid and N-substituted barbituric acids; β-iminoemides, for example 1-phenyl-3-methylpyrazol-5-one, 1-hydroxyinethyl-3-methylpyrazol-5-one, 2-iminobarbituric acid and 1- (aB "aphthyl) -3-methylpyrazol-5-one. Similarly, azo dyes are obtained when methylphenylpyrazolone is replaced by other heterocyclic couplers. Such couplers include 1-phenyl-5-pyrazolone; 3-methyl-5-pyrazolone; 3-ethyl-5-pyrazolone; i-phenyl-3-ethoxycarbonyl-5-pyrazolone; i-phenyl - ^ - butoxycarbonyl-5-pyrazolone; 1-phenyl-3-phenoxycarbonyl-5-pyrazolone; 1-phenyl-S-carbatnoyl ^ pyrazolone; i-phenyl ^ -methylcarbamoyl-S-pyrazolone; 1-phenyl-3-dimethylcarbamoyl-5-pyrazolone; 1-phenyl-3-phenylcarbatnoyl-5-pyrazolone; 1-phenyl-3 ~ (2 »hydroxyethylcarbamoyl) -5-pyrazolone; 2-methylindole; 5-bromo-2-roethylindole; Carbazol-2-ol? 3-dibenzofuranol; 5-quinolinol; 8-quinolinol; 5-isoquinolinol; 2,4-quinolinediol; 1- (ra-nitrophenyl) -3-methyl-5-pyrazolone; 1-Fe-Nitropheny ^ -3-raethyl-5 «pyrazolone; 1,2,3,4-Tetrahydro-6-methoxyquinolines 1,2,3,4 ~ Tetrahydro-7-ynethyl-

20981 7 / U51
- 19 -

OR-4729

quinoline; 1,2,3,4-tetraliyaro-i-raethylcmnoline; 1,2,3,4-tetrahydro-1- (2-hydroxyethyl) quinoline; 3,4-dihydro-2H-1,4-benzoxazine (benzomorpholine); 4-ethyl-3,4-dihydro-2H-1,4-bensoxa-r interest; 4- (2-cyanoethyl) ~ 3,4-dihydro-2H-1,4-benzoxazine julolidine; 2-acetamide othiophene, 2-benzamide othiophene, 2-bimethylaminothiazole; Indazol-6-ol; 2-phenylindole; 1-dimethylarainomethyl-3-raetliylpyrazol-5-one and 1,3,3-trisniethyl-Δ, α-indoline.

Existing tertiary amine coupling components can with the diazo compounds to form dyes for anionic fibers, or these couplers can first in their quaternary ammonium derivatives with suitable reagents and then to diazo compounds coupled to supply cationic dyes. Some typical examples of both types of couplers are explained below:

/ 2- (N-methyl-3-ethylanilino) -ethyl7-trimethylammonium chloride; ^ - (N-butyl-m-anisidinoJ-ethylZ-triethylammonium chloride; benzyldimethyl ^ -2- (N-cyanoethylanilino) -ethyl7-ammonium chloride; / 2- (IT-2-hydroxyethyl-2-chloro-5-methyl8nilino) -äthylj -trimethylammonium chloride; benzyldimethyl- / 2- (lT-2-cyanoethyl8nilino) -ethyl7-ammonium chloride; / 2- (FA "thyl5-chloro-5-methoxyanilino) -ethyl / -2-hydroxyethyldimethylammonium chloride; diethylmethyl- / 2- (o- anisidino) ethyl7'-ammonium methosulfate; diethylmethyl _/ ^ 2- (5-chloro-o-anisidino) ethyl7-aratinonium methosulfate; diethylmethyl / 2- (2,5-dimethoxyanilino) ethy ^ -amraonium methosulfate; diethy! methyl ~ / 2- (5-methyl-oanisidino) -ethyl7-amnonium methosulfate; / 2- (N-ethylanilino) -i-methylethyl-trimethylammonium chloride; / 3- (N-methyl-1-mtoluid ino) -2-methylpropyl7-trimethylainmonium chloride; / 4- (F-ethyl-m-anisidino) -butyl7-trimethylamydonium chloride; diethyl methyl- / 3- (II-ethyl-m-toluid ino) -propyl7-ammonium methosulfate and 2- (F-ethylanilino) -ethyl7-trimethyl-

- 20 -

209817 / U51

OR-4729

ammonium chloride % 3 ~ (üT ^ Xthyl ^ is-toluiöino) «» 2-hydroxypropyl-> trimethylammoniumchlorldj 3- (F-ethylanilIno ~) «2-hydroxypropy It rime thy lammoniuto chlorid j / l« Cii «-Methyl = -3 ~ methane ™

sulfate; / 2- (o-chloroanilino) -ethyl / -diathylinetliylammoniummethosulfat; N _> iT,! T ⁱ -IDriethyl <~ H ' ⁸
F-Benzyl-N · -äthyl-lf-methyl »! · -Phenyl enta min 5 ethyl-U'-m-tolyläthylendlaiBin? Ή, N ~ 3) ethyl «» N ⁸ ~ iae thy! Phenylmethylenediamine; 3- (K-ethyl-m-toluieno) «2-hydro3i: propyl diethylamine; BT, F-diethyl "li ^e " (o-chlorophenyl) -ethyfenediamine; N, N, IT ^f -Ir iäthy 1-N * = pheny! Propylenediamine; N, N-diethyl-lii- (o-bromophenyl) -äthylenediarains N, ET-dixaethyl-H ^f -äthyl-N * - (2-iaethoxy-5-acetaiaidophenyl) -äthylenedian5in; N-lthyl-U- (2-hydroxyethyl) -N'-methyl-Ii ^l -phenyläthylendiasiin; IT, IT- ^ ipropyl-N * - (2-cyanoethyl) -H »- (3-ethy! Phenyl) -äthylend iamln; U, N-diethyl-ir * - (2-hydroxyethyl) -F · - (m-chlorophenyl) ethylenediamine; lf, li-I> iäthyl-] ir ^t -äthoxyäthyl ^i-N "(2-inethyl-5-methoxyphenyl) -äthylendiamIni U, F-dimethyl-N * -nethyl ^β-Ii" methyl-N · (2.5 dimethoxyphenyl) ethylenediamine; UT ₅ K ^- , ΪΤ ¹ -TrismethyliT ^f - (2-methyl-5-benzenesulfonamidophenyl) -propylenediamine N, ir-Dlmethyl-ir '-ethyl-ir * - (3-butyramidophenyl) -ethylenediamine,

Amine couplers other than tertiary aromatic amines can also be used, provided they cannot be diazotized or are difficult to diazotize under the process conditions of the invention. The suitability of a particular combination of a diazotizable amine, as described above, with a potentially diazotizable coupler compound, as explained below, can easily be determined by experiment. Some non-tertiary amine couplers of this type that can be used ₉ include 7-amino-i-naphthol sulfonic acid, 8-anilino-t-naphthalenesulfonic acid, 8-p-toluidino-1-nephtha-sulfonic acid, and 6-anilino-i -naphtholsulfonic acid. Under the conditions

- 21 -2Q9Ö17 / 1451

According to the invention, the amino-substituted couplers which also carry phenolic hydroxyl groups couple, preferably in the ortho or para position to the amino function (not to the hydroxyl group), an unsubstituted position should also be available in the ortho or para position to the hydroxyl group.

The reaction mixture used according to the invention should have a pH of 4.0 or lower (determined by diluting a sample of the reaction mixture with 25 % of its volume of water). In some cases, the method can be carried out at a pH of 0.1 but the pH is preferably in the range of 2 to 4. Buffers can optionally be used to maintain the pH within the desired range. Suitable buffers include salts of bases and acids with lower ionization constants than the bases, for example disodium phosphate, sodium acetate, calcium citrate, aluminum tartrate or sodium borate.

It should be noted that the reaction mixture described above forms and has such acidity and temperature, that the desired azo dye is formed virtually instantaneously, that improper accumulation of unreacted normally heat-sensitive diazonium compounds in the reaction mixture avoided will. For this purpose, the course of the reaction can be easily monitored by following the appearance of the colored Product using. Thin layer chromatography techniques registered. If necessary, the disappearance of other reaction components can be followed by standard experiments will.

Preferably, the above conditions are so

- 22 209817/1451

OR-4729

set that practically immediately after being brought together of the diazotizing agent of the diszotatable amine and the coupler in the liquid acidic medium neither that Diazotizing agent still to determine the diazotized Atnin are or can only hardly be determined in the reaction mixture. In other words you want speed the consumption of the diazotizing agent and the formation rate of the azo dye are practically the same be.

In general, couplers combination amine can the choice of the diazotizing agent and the acid for a given and _s are varied their ratio in the Reaktionsgemiseh prepare suitable coupling conditions. Likewise, the nature and proportion of the liquid component of the mixture can be varied widely to solubilize the reactants according to the requirements set out above, so that the formation of azo dye is facilitated in good yield and high purity. For example, with coupling components, the basic tertiary amine groups, an aqueous acid, for example, suitable _y 10 #ige hydrochloric acid or an organic acid such as formic acid, acetic acid or propionic acid. In the case of active methylene compounds, it is very useful to use acidic organic media, such as the above carboxylic acids, preferably acetic acid, and to keep the pH at 2 to 4. It is often advantageous to use an organic solvent together with the carboxylic acid, such as, for example, N ₅ N-dimethylformamide or Ν, Ν-dimethylacetamide. In addition to their dissolving action, alkylcarboxamides provide a buffering action and facilitate the coupling reaction.

- 23 -

209817/1451

QR-4729

The speed with which the diazotization agent to be brought to the "Ferbstoffkomponenten into contact, ah., The concentration that are intended to maintain in the reaction mixture depends on the availability of dissolved diazotizable amine and the availability of the dissolved coupler for Beendigungiler formation of the azo dyes from. Preferably, the diazotizing agent should be added about as quickly as it can be consumed to form the azo dye If nitrous acid is formed in the liquid medium, such as by adding a 30% solution of sodium nitrite, the addition time can be in the range of a few minutes The required speed can easily be determined by simple experiments, for example using an iodine starch reagent.

The invention is normally carried out at a temperature of from 0 to about 30 ⁰ C ₁ preferably at 10 to 25 ⁰ C. The temperature of the reaction mixture may rise up to about 100 ⁰ C, but preferably not more than 35 ⁰ C * Where high concentrations of Reakäonsteilnehmern be applied (25> or above i), external cooling can be applied for temperature regulating Lung; Lower reactant concentrations (below 20 #) require little or no cooling.

The invention enables higher concentrations of reactive components to be used and more concentrated ones to be formed Azo dye reaction mixtures than previously possible because of the use of separate amounts of Avoided diluents for each azo dye component will. It is advisable to use reaction mixtures which contain more than 50% paraffin coraponents in solution. Higher concentrations can be used

- 24 209817/1451

2133311

OR-4-729

is

without the need for complete dissolution of the dye components. The use of an aminoazo compound as a diazotizable amine generally requires that the reaction mixture be more dilute with respect to the azo dye component. Preferred ranges of Asofarbstoffkomponenten in the reaction mixture are 15 to 40 $> in the EaIl Monoazofarbstoffbildung, 8 to 15 #, in the case .the azo dye.

The high concentration of reactants useful in this process enables the formation of dyes in larger particle sizes than by multistep processes. The particles are formed at an early Seitpunkt during the process and to grow, with increasing formation of the dye. The dye particles produced can be 40 times the size of particles produced by multi-step processes. The larger dye particles obtained have much better filterability and retain less liquid medium. Azo dyes formed from complete solutions of azo dye components often produce the largest dye particle size and have the most favorable filterability, the highest solids content and the lowest content of dye impurities. Decomposed diazotized amines are not noticeable in dyes * which are produced in this process _9.

Dyes produced by this process are suitable dyes for dyeing synthetic and natural materials,

- 25 209817/1451

OR-4729

such as polyacrylonitrile, polyamide and polyester fibers, cotton and their mixtures and wool, with known ones Standard methods are used.

In the following examples, parts and percentages relate to on weight, unless otherwise stated, with the exception of where parts refer to volume, in which case the volume is that of the same proportion parts Water is ingested. The colors given for the dyes produced are the colors that appear on polyester fibers unless otherwise stated.

example 1
Production of

NO

A solution of 150 parts of water, 13.9 parts of 3-nitroaniline, 12.7 parts of Ν, Ν-dimethylaniline and 34, 5 parts of 37 W #iger hydrochloric acid was cooled to ⁰ ° C. 48 parts of 15 # sodium nitrite solution were added steadily over 1/2 hour. A reddish brown precipitate formed

The mixture was stirred for a further hour at 0 to 5 ^° C., then for 2 hours with warming to room temperature. The precipitate was filtered off. The filter cake was washed with 50 parts of 1% hydrochloric acid, then with water until the filter cake was acid free. 38. Parts

- 26 -

209817/1451

OR-4729

moist filter cake containing 59 ί ° solids was recovered.

After drying, the filter cake was an orange powder. A! Recrystallized from isopropyl alcohol sample melted at 149-150 ⁰ C and had the same melting point * in Gemisch'mit a product that has been obtained by coupling a separate diazo compound of the 3-nitroaniline with Ν, Ν-dimethylaniline. The infrared absorption spectrum of the recrystallized dye and the comparative product were identical.

Example 2
Production of

(CH ₂ CH ₂ OCOCH ₃ ),

NHCOC ₆ H ₅

A solution was formed from 38.4 parts of 3-ZBis- (2 ^l = -acetoxyethyl) -aminoj-benzanilide, 51.7 parts of glacial acetic acid, 17.42 parts of 2-chloro-4-nitroaniline and H ₉ 8 parts of 37% hydrochloric acid . The solution had a volume of 120 parts.

Was controlled while the temperature of the solution by Eissiagabe to 25 to 28 ⁰ C, 28.2 parts of 25 $ aqueous sodium nitrite solution for 60 mimed added. Before filtration, the volume was 160 parts and the pH was 0.4. The Reaktioasgeraieeh wh? Ö © filtered ^ nnd the solids were dissolved with water. 118 parts of filter cake

- 27 • 209817/1451

OR-4729

yielded 54 "3! Peile dry cake which contained 82% Azofarbstof {which was identical with the red dye!, by the coupling of 3-ZBis ~ (2 ^t -acetoxyäthyl) -eminq7-benzanilide with separately diazotized 2-chloro- 4-nitroaniline had been obtained. When equal amounts of diazo and coupler components were coupled by a conventional aqueous multistep process, the reaction mass had a volume of 710 parts.

Example 3
Production of

VN = Ii- / V- N (CH ₂ CH ₂ OCOCH ₅ )

NHCOC ^ H _n

A solution was prepared from 38.4 parts of 3- ^ bis (2 ^f -acetoxyethy3) -, aminoj-benzanilide, 13.95 parts of 4-nitroaniline, 45.5 parts of glacial acetic acid and 13.9 parts of 37% aqueous hydrochloric acid. The solution had a volume of 27 parts.

28.2 parts of 25% strength sodium nitrite solution were added to the solution over the course of 15 minutes, while it was kept at a temperature of 25 ^° C. by adding ice. The reaction mixture obtained had a volume of 160 parts and a pH of 0.1. 98.4 parts of the filter cake gave 52.4 parts dry cake containing 89.6 $> of azo dyes, which was identical with the product in that by coupling 3 / bis (2'-acetoxyethyl) -aminoy-benzanilide with separately diazotized 4-nitroaniline had been obtained in a conventional aqueous multi-step process.

- 28 209817 / US1

OR-4729

The preparation of this dye from equal amounts of diazo and coupler components by conventional aqueous multi-stage process resulted in a reaction mass with a volume of 525 parts.

Example 4
Production of

A suspension of 100 parts of water, 19s2 <'.! Peilen K ~ (2-cyanoethyl) -F ~ ethyl-iD ~ toluidine, 17 ₉ 5 files 2-chloro-4-nitroaniline and 24 _s 6 ropes 37 figured chlorine was obtained - "Hydrogen acid produced", the slurry had a volume of 150! parts ".

28.0 ropes of 25 # aqueous sodium nitrite was added to the stirred slurry over 90 minutes. No ice was added. The reaction mixture had a volume of 175 liters and a pH value of 1 ₉ 5 «

The reaction mixture was stirred for an additional hour and filtered. The solids were washed with water. 114 Ropes press cake were 28 ₉ 5! Ropes dry Iuchen _s the 75 ■■ $> azo dye contained "was equivalent to the purified Asofarbstoff from the usual aqueous multistage process using the above diazo and coupling components. The Reaction Maes® from the multistage process had a volume of 800 parts.

- 29

209817 / U51

OR-4729 SO

Example 5

16 parts of N-cyanoethyl-F-methylaniline and 14 parts of 4-lfitroanilin were slurried together in 105 parts of glacial acetic acid at 20 to 30 ⁰ C. During 1 1/2 hours, 30 parts of aqueous 30 #iges liatriumnitrit added slowly at 20 to 30 ⁰ C. No cooling was applied.

The mass was stirred for an additional 2 hours and then diluted by the slow addition of 50 parts of deionized water. The slurry was filtered and the filter cake washed free of acid. The filter cake was ^{dried at 0} ° C. 28 parts of dry cake containing $ 94.8> dye and identical to purified orange azo dyes obtained by a conventional aqueous multistep process was obtained. The multistep aqueous process produced a reaction mixture having a volume of 550 parts.

Example β

20 parts IT, If-bis (eyanoäthyl) aniline and 18.0 T _e ile 2-chloro-4-nltroanilin were slurried in 100 parts water. 29 »5 parts technical grade concentrated hydrochloric acid were added to the slurry. To this slurry, 30 parts of aqueous 30 #iges Nätriuranitrlt added at a temperature of the reaction mixtures 20 to 30 ⁰ C slowly over 1 1/2 hours. No cooling was applied.

The mass was stirred for a further hour at 20 to 30 ^° C. and filtered. The solids® became acid-free with water

209817/1451

OR-4729

washed and then " ^{dried at 70 0} G" 29 parts of dry dye were obtained, the 78.8 % azo dye of the formula

(CH ₂ OH ₂ GIi) ₂

contained, the polyester fibers by disperse dyeing methods colors in orange tones «,

Example 7

20.7 parts of 2,6-dichloro-4-nitroaniline (O ₅ 1 mol) were and 29.4 parts of N-cyanoethyl-N-benzoyloxyäthylanilin slurried in parts glacial acetic acid at 20 to 30 ⁰ C. 30 parts of 30% aqueous netrium nitrite were slowly added over 11/2 hours. No cooling was applied

The mass was then stirred for 2 hours and then filtered. The filter cake was washed with a mixture of gmehen parts Washed water and glacial acetic acid until the filtrate was clear, then washed with water until it was acid free. 32.5 parts dry product was obtained, a brown azo dye of the formula!

Q ₂ SM V_N = N

When this azo dye was prepared by diazotizing dichloroitroaniline with nitrosylsulfuric acid and coupling in aqueous acetic acid in a multistage process, a toluene was produced from 1350 ropes of reaction mixture "

209817 / 14.51

OR-4729

Example 8

56 ropes (0.24 mol) of aminoazobenzene hydrochloride were prepared in a solution of 78 parts (0.2 mol) of N, N-di- (2'-benzoyloxyethyl) aniline in 850 parts of glacial acetic acid. A solution of 20.7 parts (0.3 mol) of sodium nitrite in 250 parts of water was added to the suspension for 4 hours while the temperature of the mixture warde adjusted to 18 ⁰ C. The dye formed immediately after the addition of nitrite. After about 10 # of the nitrite had been added, 0.03 part of the expected product was added to seed the dye.

After another hour at 16 ⁰ C, the batch was filtered and washed with 60 #iger aqueous acetic acid. The filter cake was reslurried in water, filtered again and washed with water. 180 parts of dry cake were obtained, 93 Ί »of which was pure orange dye of the following formula:

f \

f ~ \

N = N

r \

-N (CH ₂ CH ₂ OCOC ₆ H ₅ ),

0 example 9

20981 7 / U51

It was a solution of 16.25 parts of 2 ~ Hltro-4-methylaniline, 30.0 parts of benzoylacet-cc-naphthamide, 110 parts of dimethylformamide and 220 parts of glacial acetic acid.

24.8 parts 30 5 weight aqueous sodium nitrite was added to the solution over 60 minutes unterHihren while dei temperature was maintained by external cooling to 20 to 25 ⁰ C. Stirring was continued for an additional 30 minutes.

The reaction mixture was filtered. The filter cake was washed with 25 parts of cold glacial acetic acid then with hot water until the wash water against Congo red test paper did not change color. After no more liquid separated, the filter cake was collected and 41 '6 parts' were obtained dry cake containing 91 # yellow azo dye. which was identical to purified dye which was through Coupling of diazotized ^ 2-nitro-4-methylaniline and benzoylacet-a-nagthamide obtained by a conventional azo coupling process.

Example 10

In this example, the produced azo dye possessed following formula:

a solution of 23.2 parts of 4-amino-3,2 ^f -dimethylazobenzene and 50.2 parts of 3rZBis (2'-benzoyloxyethyl) -amini ^ benzanilide, 315 parts of glacial acetic acid and 295 parts of dimethylformamide was prepared.

- 33 209817/1451

OR-4729 3 ^

9.9 parts of sodium nitrite dissolved in 19 parts of water were added to the solution at 25 ^° C. over the course of 15 minutes. The mixture was stirred for 16 hours longer and then filtered.

The filter cake was washed with 100 parts of glacial acetic acid and then with water. 173 parts of filter cake containing 36.6 # solids were recovered after the liquid flow from the filter cake stopped. The solids contained 96.6 % of the red dye which is identical to that obtained by coupling the same diazotized amine and 3- / Sis (2 ^f -benzoyloxyethylamino7-benzanilfi by a conventional azo coupling procedure.

Example 11

21.7 parts (0.1 mol) of 2,6-dichloro-4-nitroaniline and 40.7 parts (0.1 mol) of N, li ~ bis (2 ^l -benzoyloxyethyl) -m-toluidine were in 360 parts 88 #iger formic acid slurried. At a temperature of 20 ^° C., which was maintained by a water jacket, a solution of 10.3 parts (0.15 mol) of sodium nitrite was added to 20 parts of water over the course of 30 minutes. The stirring was continued at 20 to 25 ^° C. for a further 2 hours. The product was filtered, washed acid-free with water and dried. There were 35 parts of the brown dye

V) -N (CH ₂ CH ₂ OCOC ₆ H) _a

obtain.

- 34 -

209817/1451

OR-4729

2133311

Example 12

A suspension having a temperature of 25 ⁰ C was prepared from 390 parts of glacial acetic acid, 22.9 parts of 2-chloro-4-nitroaniline, 66.3 parts of m-Benzamidophenyldiäthanolamindibenzoat and 39 parts produced 31 #iger hydrochloric acid.

A solution of 9.7 parts of sodium nitrite in 250 parts of water was added to the stirred suspension over 1 hour. The temperature of the mixture rose to 35 ^° C. and was kept there by a surrounding water bath during the addition. The dye formed immediately after the addition of nitrite.

Stirring was continued for 2 hours at 35 ⁰ C and the mixture was filtered, washed lait glacial acetic acid and washed with hot water (70 ⁰ C) until the Eiltrat no color and no acid showed.

78 parts of dry cake were obtained, the 94 red dye of the formula

N = N

(CH ₂ CH ₂ OCOC ₆ H ₅ ) J.

contained.

Example 13

In this example, the produced azo dye possessed

- 35 209817 / U51

OR-4729

following formula

213S311

2 ^H 4 CH ₃

A solution was prepared from 2.5 parts of 2-amino-4,5-diphenylthiezene, 3.6 parts of 2- (N-ethyl-ni-toluidine) ethyl7-diethylmethylannonium methosulfate and 47.5 parts of glacial acetic acid. Sodium nitrite (2 parts of a 5N NaNO ₂ solution) was added to the solution of the coupler and diazo components at 20-25 "C over 2-3 minutes. The reaction mixture was stirred for 30 minutes. 125 parts of water were added and the temperature . was raised to 70 ⁰ C A geefittigte sodium iodine id solution (2 parts) was dee with stirring to precipitate basic dyes were added after cooling and filtration, 2.7 parts of red dye were recovered;. the product dyed Orion, polyacrylonitrile in red shades.

Example 14

he

^C 6 ^H 5

-36 209817 / U51

OR-4729

A solution was prepared from 5 parts of 2-araino-4 _s 5-diphenylthiazole, 2.4 parts of methylaniline and 71.5 parts of glacial acetic acid. Sodium nitrite (4 parts of 5N aqueous solution) was added to the reaction mixture at 20 to 25 ^° C. over the course of 2 to 3 minutes with stirring. The reaction mixture was stirred and cooled with ice water for 15 minutes and then poured into excess water. The precipitated dye was filtered off. The red dye recovered was 5.6 parts.

Example 15

_N - _N __ // \\ _ N ^ CH ₂ CH ₂ CN);

A solution was prepared by heating a mixture of 2.5 parts of 2-amino-4,5-diphenylthiazole, 2.0 parts of N, N-bis (2-cyanoethyl) aniline and 38 parts of glacial acetic acid. The mixture was cooled to 25 ⁰ C, and 2 parts of aqueous 5N sodium nitrite was added during 2 to 3 minutes. The reaction mixture was stirred at Eisteraperatüren for 15 minutes and then poured into an excess of water; the precipitated dye was filtered off. The orange dye recovered was 4.3

Example 16

In this example, the produced azo dye possessed following formula

- 37 -

209817 / U51

| 2 ^H 5

- N-CH ₂ CHChJn (CH _{3) 3}

OH

A mixture of 13β parts of 8.3 5% aqueous solution of p-arenophenacyltriraethylammonium chloride, 15 parts of 10n-hydrochloric acid and 31.1 parts of 47% aqueous solution of 3 ~ (N-ethyl-m-toluidino) -2-hydroxypropyltrimethylaromoniuraolilorid was cooled to 0 to 5 ^{0 C.} 10 parts of aqueous 5N sodium nitrite were added in one portion. The temperature rose to 10 ^° C. and a deep red-brown solution was formed. The mixture was heated to 20 to 25 ⁰ C, and the pH value was prepared by adding 7.5 parts Katriumacetat 4 eingestallte 20.3 parts of sodium fluoroborate was added to the reaction mixture. The reaction mixture was allowed to let the dye precipitate for 3 hours. The reaction mixture was filtered. The press cake obtained was washed with 300 parts of 10% aqueous sodium fluorate solution and then with 155 parts of isopropanol. The dried red-brown cationic dye obtained was 28.8 g; λ max. 490 m αι. The dye yield based on the diazo components was $ 84.4 · The product dyed acid-modified nylon in red shades.

Example 17

The azo dye prepared in this example had the following formula

- 38 -

209817 / U51

-C-IL • -N (CHa) ₃ Cl.

A device was prepared from 4.09 parts of 2-cyeno-4-nitroaniline, 15 * 5 parts of 40% aqueous solution of 2- (N-ethylanilino) -äthyltrimethylBmmoniutnchlorid, 12.3 parts of iopropenol and 5.5 parts of concentrated hydrochloric acid. The mixture was cooled to 70 ⁰ C and warmed euf 10 ⁰ C overnight; 11.25 parts of water were added, then 1.75 parts of sodium uranium nitrite in 3.5 parts of water were added over 4 hours. The reaction mixture is stirred for 1 hour and the precipitate is filtered off. The product was washed with aqueous sodium chloride. A second crop of product was obtained from the piltrate. The combined yields totaled 3.2 parts. The solid red dye product colored polyacrylonitrite in red shades.

Example t8
The dye of this example had the following structure

It was a solution of 0.92 parts of 5-chloro-3-aminobenzisothiazole, 0.9 parts of N-methyl-H- (2'-cyanoäthylj-aniline and

- 39 -

209817/1451

OR-4729

38 parts of glacial acetic acid. The mixture was ^{cooled to 15 °} C. and part of an aqueous 5N sodium nitrite solution was added. The reaction mixture was stirred for 1 hour at 10 to 15 ⁰ C, filtered, the bluish purple dye was collected, washed with 50 parts v / ater and dried; 1.6 parts were obtained.

Example 19
The dye of this example had the following structure

° 2 ^H 5

W = N χ '^ VNO ₂ H ^ -N (CH ₃ ) ₃ 01

A solution of 18 parts of o-chloro-p-nitroandLin, 59.4 parts -äthyltrimethylammoniumchloridlösung 44 #iger aqueous 2- (N-Äthylanilino) and 48 parts of isopropanol, was prepared at 40 to 45 ⁰ C. While cooling, 21 parts of concentrated hydrochloric acid and 45 parts of water were slowly added. The reaction mixture was cooled to 10 ⁰ C, and there were 23 parts of 30 #iges aqueous sodium nitrite was added in 2 hours with stirring at 10 to 15 ⁰ C. After stirring the mixture for a further hour, the temperature was allowed to rise to 20 to 25 ^° C .; the precipitated red dye was filtered off, washed with 8% aqueous saline, dried and collected; the yield was 89.6% (39.8 parts from $ 100 dye).

- 40 -

209817 / U51

OR-4729

Example 20

The dye of this example had the following structure

CH ₂ -N- (C ₂ H ₅ ) ₂ 2Cl

It was a solution of 13.4 parts of bis (2 "-8minQiraldasolium)" sulfate ", 30 parts of water, 30 parts of concentrated hydrochloric acid, 26.4 parts of N-lthyl-N ~ (3 ^t -diethylainino-2'-hydroxypropylj- m-toluidine prepared. 20 ropes aqueous 5N sodium nitrite were excellent yellow 5 ⁰ G to the amber leaktionsgeinisch for 5 minutes at 0 to.. The temperature rose to 15 to to 20 ⁰ C. The Reaktioasgemisch was cooled to 0 to 5 ⁰ G. and then stirred for 1.5 hours while slowly warming to 20 ⁰ C "a Dünnsohichtchromatogramm on silica gel with a portion of the reaction mixture gave, after elution with a mixture of Ithylacetat / acetic acid / water (ratio 1: 1: 1) a red spot that that of was equivalent to that obtained from a sample of the same dye independently prepared by a conventional two-step process. The resulting liquid dye product dyed acid-modified nylon carpet fibers in orange shades.

© Il

(CH ₃ ) ₃ NCH ₂ C

Example 21

N-CH ₂ CH-CH ₂ H (CH _{3) 3}

OH

- 41 -209817 / US1

A solution of 136 parts of 8.4% aqueous solution of p-atoinophenacyltrimethylami- nium chloride, 15 parts of concentrated hydrochloric acid and 31.1 parts of ^ - (N-ethyl-m »toluidino) -2 ~} iydroxyprpyl7-triDethylaiDmoniuniclilorid was prepared. The temperature was adjusted to 5 ⁰ C, and 10 feile wäosrlges 5N sodium nitrite added. Fold lOminütigera stirring bsi 10 to 15 ⁰ C was seen in eine® Bonn eh lehtchrosat ο gmrn (silica gel) of the Heaktionsgaraisehis, which was eluted with a Geraisch from Ithylacetat / acetic acid / water ^ Yarhältnis 1s1? 1), voter Farbstoffο was allowed to reaction mixture to warm to 20 to 25 ⁰ C, uaä © s, 20 part © isopropanol. The pH of the Resktionsgemiselia was adjusted to 4, and the GeMgeh was kit sodium fluoroborate at 7.5 % w / v. aiasge sal sen. With stirring for 3 hours, the crystallized dye was filtered off with 5-hour aqueous sodium fluoroborate water : the amount of red dye was 27 * 7 g (88% in theory); λ max, 490 m * χ The dye stained synthetic fibers fixed in a red color.

Example 22

SO ₃ Na MCOC ₆ H ₅

Ss, a ßemisch h of 24 parts of 4- ^G chloro-tsetanilinsäure, 34 parts of 3 ^l ~ MmethylsrainoDsnzaniIiä and 300 parts of water at 35 "C. 7 feile Natriunnltrit were added to the

elii added over 1 hour. It formed

209817/1451

OR-4729

Immediately a precipitate of color. At the end of the reaction, the mixture was "basified. The" oily product formed on basifying crystallized upon further stirring. The orange crystalline dye was filtered ”. The dry dye was 42 parts of product (88 %> theoretical yield;) dyed nylon fibers in bright orange shades »

Example 25

Production of

HIIa

O ₂ N-

A mixture of 13.8 parts of p-nitroaniline, 30 parts of concentrated hydrochloric acid, 26.9 parts of 7-amino-i-naphtholsulfonic acid and 286 parts of glacial acetic acid was prepared. At a temperature of 21 ^° C., 21.2 parts of 5N aqueous sodium nitrite were added dropwise over the course of 10 minutes. There was no cooling applied during Nitrit_2ugabe and the temperature rose to 25 ⁰ C. The reaction mixture was stirred for 3 hours and then filtered. The cake was washed with 500 parts of water and dried. The red product was 36.6 parts of dye of the above formula (89 ° yield of theory λ max 550 m / α,

-1 - 1 \ '

Absorbency 56.5 1 g cm); it produced red Color shades on Ifylon carpet fibers.

This example illustrates the use of a coupler-the ^ a relatively difficult to diazotize amino group in

- 43 -209817/1451

Combination with an amino group that is easier to diazotize contains. Under the conditions described, the p-nitroaniline preferably diazotizes. Perner couples that diazotized p-nitroaniline under the acidic conditions used in ortho division to the amino group rather than in Para to the hydroxyl group of the naphthalene ring.

Example 24

9.7 g of aniline and 28.4 g of 1-p-sulfophenyl-3-methyl-5-pyrazolone were _{stirred into 2.8% strength by weight aqueous hydrochloric acid (300 ml of H 2} O, 20.5 ml of concentrated HCl) . Aqueous irisodium phosphate (25 g in 100 g water) was added to raise the pH from 0.6 to 3.5 so that most of the sulfopyrazolone dissolved. The mixture was ^{cooled to about 7 °} C. with stirring, and 5N aqueous sodium nitrite was added dropwise over a period of 20 minutes.

The characteristic of the expected azo compound. Color developed almost instantly. Examination of the reaction mixture by adding nitrite showed that the nitrite reagent was consumed about as quickly as it was added, and the presence of free diazo compound was barely noticeable. The pH rose slowly as the nitrite was added and small amounts of concentrated HCl were added periodically to maintain the pH between 3.5 and 4.0. The addition of nitrite was discontinued after slightly more than a molar proportion of nitrite had been added, and tests for nitrite and diazo compound were positive. The final temperature was about 10 ⁰ C. The reaction mixture was diluted with water to the partially precipitated red orange 4 1-psulfobenzol-3-methyl-5-hydroxypyrazole-Benzolazo-solubilize.

- 44 -209817/1451

Barium chloride was added to the product as a barium varnish to fail. The varnish was filtered off.

Example 25

The single-stage coupling according to Example 24 was repeated in an organic medium. A mixture of 9.7 g of aniline, 28.4 g of ip-sulfophenyl - ^ - methyl-S-pyrazolone, 150 ml of glacial acetic acid and 15 ml of Ν, Ν-dimethylformamide was cooled ^{to 20 °} C. with stirring. The pH of the reaction mixture (determined after diluting a sample with about 25 # of its volume of water) was about 2, this high degree of acidity being largely due to the sulfo compound, a strong acid. Then 5N aqueous sodium nitrite was added dropwise at a rate of about 35 ml / h »The initially brownish-yellow reaction mixture went after the introduction of Hitrite, which was consumed as quickly as it was added (negative iodine starch tea)» to yellow over * there was no free Diazo compound can be determined (negative Fleek coupling spot). After practically all of the nitrite had been added, 100 ml more acetic acid were added to dilute the mixture. The reaction was judged to have ended after about 22 ml of aqueous nitrite had been added. The pH was about 2.5 »

The reaction mixture which contained the red-orange-colored coupled product was completely soluble in water and formed a solution from which a red-yellow bake precipitated _{after the addition of BaGIi 9.} The paint was filtered off *.

C.

In each of the above examples, azo tanning agent formation occurred immediately after adding nitrite to the acidic reaction

- 45 209817/1451

tion mixture a. This is made possible by the virtually instantaneous disappearance of the diazotizing agent (more negative Iodine starch test), through development of the color characteristics of the azo dye and through the precipitation of azo dye (if the dye is in the reaction mixtures is insoluble). Under the conditions of the examples the pH of the reaction mixture was below 4.

46 -

209817 / US1

Claims (12)

Claims 1. Process for the production of azo dyes in one Step in a reaction mixture, the a diazotizable aromatic amine, a diazotizing agent and a Coupling connection contains. characterized in that the diazotizable aromatic 1min, the diazotizing agent and the coupling compound which is an active methylene compound or an aromatic amine, the is not noticeably diazotizable in the reaction mixture and has at least one unsubstituted position ortho or para to the amino group, at the same time be brought into contact in the presence of an acidic liquid medium that dissolves at least a portion of the diazotizable aromatic amine and the coupling connection is capable and is capable of generating a pH value of 4 or less, if öas reaction mixture with 25 # of its tolumen of water is diluted, the concentration of the Diazotierungsraittels and the temperature and acidity of the reaction mixture are maintained so that the rate the consumption of diazotizing agent is practically equal to the rate of formation of the azo dye. 2 »Process according to claim 1, characterized in that the β diazotizing agent is formed in the reaction mixture vird. 3 »Method according to claim 2, characterized in that the diazotizing agent by adding a nitrite salt is formed into the reaction mixture. - Al - 209817 / U51 4. The method according to claim 1, characterized in that the reaction medium contains an acid with a primary ionization constant of at least 1.3 x 10 "" · '. 5. The method according to claim 4, characterized in that acetic acid is used as the acid. 6. The method according to claim 4, characterized in that formic acid is used as the acid. 7. The method according to claim 4, characterized in that
hydrochloric acid is used as the acid. 8. The method according to claim 4, characterized in that you have a non-acidic liquid. 9. The method according to claim 8, characterized in that water is used as the non-acidic liquid. 10. The method according to claim 8, characterized in that used as a non-acidic liquid Ν, Κ-dimethylformamide will" 11. The method according to claim 1, characterized in that the acidic liquid medium is capable of dissolving at least 10 wt. Each - $> of the diazotizable aromatic amine and the coupling compound. 12. The method according to claim 11, characterized in that da8 acidic liquid medium for dissolving at least 50 wt .- ^ each of the diazotizable aromatic amine and the coupling connection is enabled. - 48 - * 209817 / U51